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<a name="Inferiors-In-Python"></a>
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<hr>
<a name="Inferiors-In-Python-1"></a>
<h4 class="subsubsection">23.2.2.16 Inferiors In Python</h4>
<a name="index-inferiors-in-Python"></a>

<a name="index-gdb_002eInferior"></a>
<p>Programs which are being run under <small>GDB</small> are called inferiors
(see <a href="Inferiors-and-Programs.html#Inferiors-and-Programs">Inferiors and Programs</a>).  Python scripts can access
information about and manipulate inferiors controlled by <small>GDB</small>
via objects of the <code>gdb.Inferior</code> class.
</p>
<p>The following inferior-related functions are available in the <code>gdb</code>
module:
</p>
<dl>
<dt><a name="index-gdb_002einferiors"></a>Function: <strong>gdb.inferiors</strong> <em>()</em></dt>
<dd><p>Return a tuple containing all inferior objects.
</p></dd></dl>

<dl>
<dt><a name="index-gdb_002eselected_005finferior"></a>Function: <strong>gdb.selected_inferior</strong> <em>()</em></dt>
<dd><p>Return an object representing the current inferior.
</p></dd></dl>

<p>A <code>gdb.Inferior</code> object has the following attributes:
</p>
<dl>
<dt><a name="index-Inferior_002enum"></a>Variable: <strong>Inferior.num</strong></dt>
<dd><p>ID of inferior, as assigned by GDB.
</p></dd></dl>

<dl>
<dt><a name="index-Inferior_002epid"></a>Variable: <strong>Inferior.pid</strong></dt>
<dd><p>Process ID of the inferior, as assigned by the underlying operating
system.
</p></dd></dl>

<dl>
<dt><a name="index-Inferior_002ewas_005fattached"></a>Variable: <strong>Inferior.was_attached</strong></dt>
<dd><p>Boolean signaling whether the inferior was created using &lsquo;attach&rsquo;, or
started by <small>GDB</small> itself.
</p></dd></dl>

<p>A <code>gdb.Inferior</code> object has the following methods:
</p>
<dl>
<dt><a name="index-Inferior_002eis_005fvalid"></a>Function: <strong>Inferior.is_valid</strong> <em>()</em></dt>
<dd><p>Returns <code>True</code> if the <code>gdb.Inferior</code> object is valid,
<code>False</code> if not.  A <code>gdb.Inferior</code> object will become invalid
if the inferior no longer exists within <small>GDB</small>.  All other
<code>gdb.Inferior</code> methods will throw an exception if it is invalid
at the time the method is called.
</p></dd></dl>

<dl>
<dt><a name="index-Inferior_002ethreads"></a>Function: <strong>Inferior.threads</strong> <em>()</em></dt>
<dd><p>This method returns a tuple holding all the threads which are valid
when it is called.  If there are no valid threads, the method will
return an empty tuple.
</p></dd></dl>

<a name="index-Inferior_002eread_005fmemory"></a>
<dl>
<dt><a name="index-Inferior_002eread_005fmemory-1"></a>Function: <strong>Inferior.read_memory</strong> <em>(address, length)</em></dt>
<dd><p>Read <var>length</var> addressable memory units from the inferior, starting at
<var>address</var>.  Returns a buffer object, which behaves much like an array
or a string.  It can be modified and given to the
<code>Inferior.write_memory</code> function.  In <code>Python</code> 3, the return
value is a <code>memoryview</code> object.
</p></dd></dl>

<a name="index-Inferior_002ewrite_005fmemory"></a>
<dl>
<dt><a name="index-Inferior_002ewrite_005fmemory-1"></a>Function: <strong>Inferior.write_memory</strong> <em>(address, buffer <span class="roman">[</span>, length<span class="roman">]</span>)</em></dt>
<dd><p>Write the contents of <var>buffer</var> to the inferior, starting at
<var>address</var>.  The <var>buffer</var> parameter must be a Python object
which supports the buffer protocol, i.e., a string, an array or the
object returned from <code>Inferior.read_memory</code>.  If given, <var>length</var>
determines the number of addressable memory units from <var>buffer</var> to be
written.
</p></dd></dl>

<a name="index-gdb_002esearch_005fmemory"></a>
<dl>
<dt><a name="index-Inferior_002esearch_005fmemory"></a>Function: <strong>Inferior.search_memory</strong> <em>(address, length, pattern)</em></dt>
<dd><p>Search a region of the inferior memory starting at <var>address</var> with
the given <var>length</var> using the search pattern supplied in
<var>pattern</var>.  The <var>pattern</var> parameter must be a Python object
which supports the buffer protocol, i.e., a string, an array or the
object returned from <code>gdb.read_memory</code>.  Returns a Python <code>Long</code>
containing the address where the pattern was found, or <code>None</code> if
the pattern could not be found.
</p></dd></dl>

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Next: <a href="Events-In-Python.html#Events-In-Python" accesskey="n" rel="next">Events In Python</a>, Previous: <a href="Writing-an-Xmethod.html#Writing-an-Xmethod" accesskey="p" rel="prev">Writing an Xmethod</a>, Up: <a href="Python-API.html#Python-API" accesskey="u" rel="up">Python API</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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